Silver halide photographic materials

ABSTRACT

A silver halide photographic material comprising at least one silver halide emulsion layer on a support, wherein the latent image distribution of silver halide grains contained in the at least one emulsion layer has at least one peak value within the grains, the location of the peak value is at a depth of less than 0.01 μm from the surface of the grains, and the average silver iodide content of the grains is about 15 mol % or less.

FIELD OF THE INVENTION

This invention relates to silver halide photo-graphic materials and,more particularly, it relates to silver halide photographic materialswhich give a good image quality.

BACKGROUND OF THE INVENTION

In recent years, there has been an increasing demand for improvedsensitivity and improved image quality in silver halide photographicmaterials.

In this regard, the internal latent image silver halide emulsions whichare to be found in U.S. Pat. No. 3,979,213 (hereinafter referred to asdocument A), The Journal of Photoqraphic Science, Vol. 13, p. 48 (1965),ibid., Vol. 22, p. 174 (1974), ibid., Vol. 25, p. 19 (1977), ibid., Vol.31, p. 41 (1986), Photographic Science and Engineering, Vol. 19, p. 333(1975), U.S. Pat. Nos. 4,035,185 and 3,850,637, and in Berichte derBunsengesellschaft for Physikalische Chemie, Vol. 67, p. 356 (1963) areoutstanding in their color sensitization properties with markedlysmaller intrinsic desensitization upon color sensitization than surfacelatent image emulsions, and additionally they are outstanding in thelatent image storage properties since the latent image is formed insidethe emulsion grain.

However, because the latent image-forming part lies deep within theemulsion grain at 0.01 μm or more, development is inadequate with theseinternal latent image emulsions even when carrying out developmentprocessing with the developing solutions for black-and-white, colornegative or color reversal photographic materials which are used inpractice and it has not been possible to produce the optimumsensitivity/granularity ratio.

On the other hand, silver halide emulsions with a high silver iodidecontent (for example, 5 mol% or more) are excellent in their sensitivityand granularity, but the storage properties of the latent image are poorand they also have undesirable tendencies such as a lack ofsusceptibility to the interimage effect, particularly with colorreversal materials, and there is a great desire for technicaldevelopments to supplement the disadvantages of such high iodideemulsions.

The interimage effect is described, for example, on pages 663 to 669 ofVolume 42 of Journal of the Optical Society of America by Hanson et al.,and on pages 106 to 118 and 246 to 255 of Volume 47 of Zeitschrift forWissenschaftliche Photographic, Photophysique und Photochemie by A.Thiels.

There have been attempts to control the halogen composition within thegrain in an endeavor to improve the color sensitization properties andthe granularity. However, there have been no specific discussions as towhat kind of halogen composition distribution is preferable within thegrain or investigations into the internal and external halogencomposition in the portion forming the latent image in internal latentimage grains.

SUMMARY OF THE INVENTION

Thus, the object of this invention is firstly to provide silver halidephotographic materials which are excellent in their sensitivity andgranularity, secondly to provide silver halide photographic materialswhich are outstanding in their storage properties, and thirdly toprovide silver halide photographic materials which are outstanding inthe interimage effect.

The above objectives of this invention are achieved by means of a silverhalide photographic material (1) comprising at least one silver halideemulsion layer on a support, wherein the latent image distribution ofthe silver halide grains contained in the at least one emulsion layerhas at least one peak value within the grains, the location of the peakvalue is at a depth less than 0.01 82 m from the surface of the grains,and the average silver iodide content of the grains is 15 mol % or less.

The above objectives of this invention are also achieved by means of asilver halide photographic material (2) comprising at least one silverhalide emulsion layer on a support, wherein the latent imagedistribution of the silver halide grains contained in the at least oneemulsion layer has at least one peak value within the grains, thelocation of the peak value is at a depth less than 0.01 μm from thesurface of the grains, and the silver iodide content of the grainsurface region is 90% or less of the average content of the wholegrains.

DETAILED DESCRIPTION OF THE INVENTION

The latent image distribution as referred to here is the depth of thelatent image from the grain surface on the abscissa (x) (x μm) and thelatent image number on the ordinate (y).

wherein: ##EQU1## S: the average grain size of the silver halideemulsion (μm) Ag₁ : the residual silver amount after subjecting theunexposed emulsion coating sample to the processing described hereafterAg_(O) : the coated silver amount prior to processing and y is thereciprocal of the exposure giving a density with a fogging of +0.2 whencarrying out the processing described below, after exposure of a whitelight for 1/100 second. The processing conditions when determining theabove latent image distribution involve adding 0 to 10 g/liter ofanhydrous sodium sulfite to a processing solution comprising:

    ______________________________________                                        N-Methyl-p-aminophenol Sulfate                                                                         2.5   g                                              L-Ascorbic Acid Sodium Salt                                                                            10    g                                              Sodium Metaborate        35    g                                              Potassium Bromide        1     g                                              Water to make            1     liter                                          pH                       9.6                                                  ______________________________________                                    

and then processing for 5 minutes at 25° C. By varying the amount ofanhydrous sodium sulfite between 0 and 10 g/liter, the depth at whichthe latent image in the silver halide grain developed during processingis to be found from the surface varies, and it is possible to determinethe variation in the latent image number in the depth direction.

This invention is explained in more detail below.

The internal latent image emulsion is subjected to developmentprocessing using a developing solution which is used forblack-and-white, color negative or color reversal photographic materialsin practice and, in order to produce the optimum sensitivity, it isnecessary to control the grain formation conditions of the emulsion andto control the location (depth) of the peak value(s) of the latent imagedistribution. It is clear that the internal latent image emulsionsoptimized in this way are not only superior to surface latent imageemulsions of an equal grain size in their blue sensitivity and theircolor sensitization properties, but they also have good latent imagestorage properties and they are capable of a good interimage effect whenused in multilayer photosensitive materials.

With emulsions with a high silver iodide content, even when the iodideions released by the development of the other layers diffuse into thelayers containing these emulsions, there is a particular tendency forthe iodide ion-induced development inhibition to decrease and for theinterimage effect to weaken. However, it is possible to sustain a largeinterimage effect when using the internal latent image emulsions of thisinvention.

The "processing solutions used in practice" as mentioned above do notinclude the developing solutions from which silver halide solvents havebeen excluded with a view to developing only the surface latent image,nor do they include the developing solutions in which large quantitiesof silver halide solvents are present with a view to developing theinternal latent image.

With the former developing solutions, i.e., those from which silverhalide solvents have been excluded, it is not possible to produce theoptimum sensitivity of the internal latent image emulsions of thisinvention, and in the latter developing solutions, i.e., those in whichlarge quantities of silver halide solvents are present, the silverhalides are overly dissolved during processing thereby deteriorating thegranularity by infectious development. Specifically, it is preferablethat the developing solutions contain 100 mg/liter or less of potassiumiodide or 100 g/liter or less of sodium sulfite or potassium sulfite asthe silver halide solvent. Apart from these, it is possible to use, forexample, potassium thiocyanate as the silver halide solvent.

The emulsions of this invention can be color sensitized by methods wellknown in the industry. The amount of sensitizing dye should be theamount with which a minus blue sensitivity maximum is obtained, and thisamount will be of the same order as that for obtaining a maximum minusblue sensitivity in surface latent image emulsions; and if the dyes areadded in much larger amounts than this, grain development is inhibitedwhich is undesirable.

The emulsions of this invention can also be used without having beencolor sensitized. In such cases, it is not possible to expect the colorsensitization effects disclosed in document A, but improvements will beobserved in the interimage effect and the storage properties.

Silver iodobromide or silver iodochlorobromide with an average silveriodide content of 15 mol % or less are used in the silver halidephotographic emulsions used in the photographic material (1) of thisinvention. These are preferably silver iodobromide or silveriodochlorobromide containing from 3 mol % to 15 mol %, and morepreferably from 5 to 10 mol % of silver iodide. For the photographicmaterial (2) of this invention, the silver iodide content in the surfaceregion of the internal latent image silver halide grains is 90% or lessof the average content of the whole grain. In the photographic material(2), there are no particular limitations on the silver iodide content ofthe silver halide grains, although it suitably is 15 mol % or less andpreferably 3 to 15 mol %.

It has become clear that when varying the surface silver iodide contentin the above internal latent image silver halide grains, the improvementin the latent image storage properties is particularly marked when thesilver iodide content in the outside of the grain beyond the vicinity ofthe location in which the latent image forms is made lower than that onthe inside. It has not hitherto been suspected from studies of thesilver iodide content in surface latent image systems that the internaldistribution in the grain has a large effect on improving thesensitivity and storage properties of such internal latent imagesystems, although it is possible to explain this phenomenon if it isconsidered that the rate at which the emulsion grains are dissolved bythe developing solution up to the position which has been chemicallysensitized is controlled by the silver iodide content of the grainsurface.

The part in which the silver iodide content is lower than the averagesilver iodide content of the grain may be: (1) only the extreme surfaceof the grain, (2) the region from outside the vicinity of the locationat which the latent image is principally formed up to the surface, or(3) the region from inside the vicinity of the location at which thelatent image forms up to the grain surface, although (3) gives morepreferable results in terms of improvement in the latent image storageproperties.

The silver halide grains may be the so-called regular grains having acubic, octahedral, tetradecahedral or other such regular crystal form,they may have a tabular, spherical or other such irregular crystal form,they may be grains having a twin crystal plane or other such crystalflaw or they may be complex forms of these.

Tabular grains with an aspect ratio of 5 or more and regular grains arepreferably used in this invention.

The silver halide grain size includes fine grains of approximately 0.1μm or less and large sized grains with projected surface area diametersof up to approximately 10 μm, or alternatively there are mono-dispersedemulsions having a narrow distribution and emulsions having a widedistribution, the monodispersed emulsions being preferred in that theyimprove the graininess.

Monodispersed emulsions are represented by emulsions of the kind inwhich at least 95% by weight of the grains are within ±40% of theaverage grain diameter. Emulsions of the type in which the average graindiameter is 0.05 to 3 μm and at least 95% by weight or at least 95%(grain number) are within the range ±20% of the average grain diametercan be used in this invention. Production methods for such emulsions aredisclosed in U.S. Pat. Nos. 3,574,628, 3,655,394 and British Patent1,413,748. Furthermore, monodispersed emulsions of the kind disclosed inJP-A-48-8600, JP-A-51-39027, JP-A-51-83097, JP-A-53-137133,JP-A-54-48521, JP-A-54-99419, JP-A-58-37635 and JP-A-58-49938 (the term"JP-A" as used herein refers to a "published unexamined Japanese patentapplication") can also preferably be used in this invention.

Production methods for so-called core/shell emulsions disclosed in, forexample, U.S. Pat. Nos. 3,979,213, 3,966,476, 3,206,313, 3,917,485 andin JP-B-43-29405 and JP-B-45-13259 (the term "JP-B" as used hereinrefers to an "examined Japanese patent publication") can be used asmethods for producing internal latent image emulsions, although with allthese methods it is necessary for the shell thickness to be 0.01 μm orless and preferably 0.003 to 0.008 μm, and to adjust depositionconditions and the silver halide amount deposited after the chemicalsensitization of the core in order to obtain an emulsion having theoptimum sensitivity/granularity ratio with the practical processingsolutions of this invention.

More specifically, in U.S. Pat. No. 3,979,213, the internal latent imageemulsion is prepared by a method in which the silver halide isredeposited onto emulsion grains with chemically sensitized surfacesusing the controlled double jet method. If the amount of silver halideused in this patent was deposited onto the grains, there would beinsufficient development with practical developing solutions and thesensitivity and granularity would deteriorate. For this reason, theamount of silver halide deposited after chemical sensitization must beless than that used in U.S. Pat. No. 3,979,213 as mentioned above.

Furthermore, a method in which silver halide is deposited onto theemulsion grains after chemical sensitization using the controlled doublejet method is also described in U.S. Pat. No. 3,966,476. However, ifafter chemical sensitization the silver halide is deposited using amethod such as that employed in this patent, it is not possible to burythe photosensitive nucleus within the grain. Accordingly, with theemulsion used in the above patent, the sensitivity will rise at leasthigher than 0.02 log E compared with the original emulsion in which thesurface was chemically sensitized even when using surface development.In order to achieve the internal latent image emulsions of thisinvention, it is, therefore, necessary to achieve what is desired byincreasing the amount of silver halide deposited after chemicalsensitization beyond that employed in U.S. Pat. No. 3,966,476 and bycontrolling the deposition conditions (for example, the solubility ofthe silver halide and the rate of addition of soluble silver salts andsoluble halide salts during the deposition).

When using the above-mentioned tabular grains in this invention, inorder to accelerate the grain growth, it is preferable to use themethods in which the rate of addition, the added amounts and the addedconcentrations of the silver salt solutions (for example, aqueous AgNO₃solution) and halide solutions (for example, aqueous KBr solution) whichare added during production are increased.

With respect to these methods, it is possible to refer to thedisclosures in, for example, British patent 1,335,925, U.S. Pat. Nos.3,672,900, 3,650,757, 4,242,445 and JP-A-55-142329 and JP-A-55-158124.

The properties of the silver halide grains can be controlled by thepresence of various compounds in the silver halide deposition formationstage. Such compounds may initially be present in the reaction vessel,or they can be added together with 1 or 2 or more salts following theusual methods. The characteristics of the silver halide can becontrolled by the presence of compounds such as compounds of Group VIIInoble metals and gold, zinc (sulfur, selenium and tellurium and othersuch chalcogen compounds), cadmium, bismuth, lead, iridium and copper asdisclosed in U.S. Pat. Nos. 2,448,060, 2,628,167, 3,737,313, 3,772,031,and in Research Disclosure, Vol. 134 (June, 1975), No. 13452, during thesilver halide deposition formation stage. It is possible to effectreduction sensitization of the inside of the grains of silver halideemulsions during the deposition formation stage as disclosed inJP-B-58-1410 and Journal of Photographic Science, Vol. 25, 1977, pp.19-27 by Moisar et al.

For the chemical sensitization, it is possible to use active gelatin asdisclosed in The Theory of the Photographic Process, 4th Ed., Macmillan,1977, pp. 67-76 by T. H. James, or alternatively it is possible to usesulfur, selenium, tellurium, gold, platinum, palladium, iridium, orcombinations of a plurality of these sensitizing agents under conditionsof a pAg of 5 to 20, a pH of 5 to 8 and temperatures of 30 to 80° C. asdisclosed in Research Disclosure, Vol. 120 (April, 1974), No. 12008;Research Disclosure, Vol. 134 (June, 1975), No. 13452; U.S. Pat. Nos.2,642,361, 3,297,446, 3,772,031, 3,857,711, 3,901,714, 4,266,018 and3,904,415 and also in British Patent 1,315,755. Most suitably, thechemical sensitization is carried out in the presence of a gold compoundwith a thiocyanate compound, or with a sulfur-containing compound, or inthe presence of sulfur-containing compounds such as "Hypo",thiourea-type compounds and rhodanine-type compounds as disclosed inU.S. Pat. Nos. 3,857,711, 4,266,018 and 4,054,457. It is also possibleto effect the chemical sensitization in the presence of auxiliarychemical sensitization agents. Compounds such as azaindenes,azapyridazines and azapyrimidines, which are known to inhibit foggingduring the chemical sensitization stage and to increase the sensitivity,are used as the auxiliary chemical sensitization agents. Examples ofauxiliary chemical sensitization agent are disclosed in U.S. Pat. Nos.2,131,038, 3,411,914, 3,554,757, JP-A-58-126526 and in G. F. Duffin,Photographic Emulsion Chemistry, Focal Press, 1966, pp. 138-143. Inaddition to chemical sensitization, or in place of it, it is possible tocarry out reduction sensitization using, for example, hydrogen asdisclosed in U.S. Pat. Nos. 3,891,446 and 3,984,249, or to carry outreduction sensitization using reducing agents such as stannous chloride,thiourea dioxide and polyamines as disclosed in U.S. Pat. Nos.2,518,698, 2,743,182 and 2,743,183 or else using a method involving alow pAg (for example, less than 5) and/or a high pH (for example,greater than 8).

In this invention, the above-mentioned chemical sensitization is carriedout after the formation of the core grains in such a way that the peakvalue of the latent image distribution is on the surface of the grainsand it is necessary to provide optimum conditions by controlling thesilver halide type, the pAg, the pH, the chemical sensitizing agentsused and other such factors.

Furthermore, after producing a shell of the above-mentioned thickness,they should preferably be set such that the latent image number on theshell surface is 1/5 or more and less than 1 time the peak value, morepreferably 0.3 to 0.6 time of the peak value. The conditions for thecontrol of the shell surface latent image number will vary dependingupon the pH, pAg, and the silver halide type used in the shell producingstage, chemical sensitization will be carried out as required.

The emulsions of this invention which are obtained from the above stagehave at least one peak value in their internal grain latent imagedistribution within the grain and the location of the above-mentionedpeak value is less than 0.01 μm and preferably 0.008 μm from the grainsurface.

A plurality of the emulsions of this invention can be mixed and used inthe same emulsion layer. Furthermore, they may be used in conjunctionwith the usual so-called "surface latent image emulsions". Furthermore,the emulsions of this invention and the usual emulsions mentioned abovecan be used singly between emulsion layers having the same colorsensitivity or different color sensitivities.

When two kinds of the internal latent image emulsions are mixed andused, and the respective average grain size ratios are 1.1 to 1.6, animproved sensitivity/granularity ratio and sensitization processing canbe obtained.

Furthermore, silver halide grains in which the ratio of surface latentimage numbers to internal latent image numbers is about 1/5 or more andless than 1 are preferably used in this invention.

The usual silver halide photographic emulsions mentioned above which areused in this invention can be prepared by known methods and, forexample, it is possible to follow the methods disclosed in ResearchDisclosure, Vol. 176, No. 17643 (December, 1978), pages 22 and 23 "I.Emulsion Preparation and Types" and in Research Disclosure, Vol. 187,No. 18716 (November, 1979), p. 648.

Noodle washing, flocculation precipitation or ultrafiltration or thelike is used to eliminate the soluble silver salts from the emulsionbefore or after the time of physical ripening.

The additives which are used in chemical ripening and spectralsensitization of the emulsions used in this invention are disclosed inthe aforementioned Research Disclosure, No. 17643 (December, 1978) andResearch Disclosure, No. 18716 (November, 1979) and their relevantlocations have been collated into the following table.

Known photographic additives which can be used in this invention arealso disclosed in the above two Research Disclosures and the locationsof their disclosures are shown in the following table.

    ______________________________________                                        Type of Additives                                                                              RD 17643   RD 18716                                          ______________________________________                                        1.   Chemical Sensitizers                                                                          Page 23    Page 648, right                                                               column                                        2.   Sensitivity Increasing                                                                        --         Page 648, right                                    Agents                     column                                        3.   Spectral Sensitizing                                                                          Pages 23-24                                                                              Page 648, right                                    Agents, Supersensitiz-     column to page                                     ing Agents                 649, right column                             4.   Whitening Agents                                                                              Page 24    --                                            5.   Antifoggants and                                                                              Pages 24-25                                                                              Page 649, right                                    Stabilizers                column                                        6.   Light Absorbers, Filter                                                                       Pages 25-26                                                                              Page 649, right                                    Dyes, Ultraviolet          column to page                                     Absorbers                  650, left column                              7.   Antistaining Agents                                                                           Page 25,   Page 650, left to                                                  right column                                                                             right columns                                 8.   Color Image Stabilizers                                                                       Page 25    --                                            9.   Film Hardening Agents                                                                         Page 26    Page 651, left                                                                column                                        10.  Binders         Page 26    Page 651, left                                                                column                                        11.  Plasticizers,   Page 27    Page 650, right                                    Lubricants                 column                                        12.  Coating Aids,   Pages 26-27                                                                              Page 650, right                                    Surfactants                column                                        13.  Antistatic Agents                                                                             Page 27    Page 650, right                                                               column                                        ______________________________________                                    

Various color couplers can be used in this invention and specificexamples of them are disclosed in the patents disclosed in theaforementioned Research Disclosure (RD), No. 17643, VII-C to G.

The substances disclosed, for example, in U.S. Pat. Nos. 3,933,501,4,022,620, 4,326,024, 4,401,752, JP-B-58-10739, British Patents1,425,020 and 1,476,760 are preferred as yellow couplers.

As magenta couplers, 5-pyrazolone-type and pyrazoloazole-type compoundsare preferred and the substances disclosed, for example, in U.S. Pat.Nos. 4,310,619, 4,351,897, European Patent 73,636, U.S. Pat. Nos.3,061,432, 3,725,067, Research Disclosure, No. 4220 (June, 1984),JP-A-60-33552, Research Disclosure, No. 24230 (June, 1984),JP-A-60-43659, U.S. Pat. Nos. 4,500,630 and 4,540,654 are particularlypreferred.

Phenol-type and naphthol-type couplers can be mentioned as cyancouplers, the substances disclosed in U.S. Pat. Nos. 4,052,212,4,146,396, 4,228,233, 4,296,200, 2,369,929, 2,801,171, 2,772,162,2,895,826, 3,772,002, 3,758,308, 4,334,011, 4,327,173, West GermanLaid-Open Patent 3,329,729, European Patent 121,365A, U.S. Pat. Nos.3,446,622, 4,333,999, 4,451,559, 4,427,767 and European Patent 161,626Abeing preferred.

The colored couplers disclosed in Research Disclosure, No. 17643,section VII-G, U.S. Pat. No. 4,163,670, JP-B-57-39413, U.S. Pat. Nos.4,004,929 and 4,138,258 and British Patent 1,146,368 are preferred forcorrecting unwanted absorption of the color-forming dyes.

Typical examples of polymerized dye-forming couplers are disclosed inU.S. Pat. Nos. 3,451,820, 4,080,211, 4,367,282 and British Patent2,102,173.

Couplers which release photographically useful residual groups duringcoupling are also preferably used in this invention. The substancesdisclosed in -the patents disclosed in the aforementioned RD, 17643,section VII-S, and in JP-A-57-151944, JP-A-57-154234, JP-A-60-184248 andU.S. Pat. No. 4,248,962 are preferred for DIR couplers which releasedevelopment inhibiting agents.

The substances disclosed in British Patents 2,097,140, 2,131,188,JP-A-59-157638 and JP-A-59-170840 are preferred as couplers whichrelease development accelerators or nucleating agents in image formduring development.

Competitive couplers disclosed, for example, in U.S. Pat. No. 4,130,427,the polyequivalent couplers as disclosed, for example, in U.S. Pat. Nos.4,283,472, 4,338,393, 4,310,618, the DIR redox compound-releasingcouplers as disclosed, for example, in JP-A-60-185950, and the couplerswhich release dyes of which the color is restored after elimination asdisclosed, for example, in European Patent 173,302A can be used in thephotographic materials of this invention as couplers.

The couplers which are used in this invention can be introduced into thephotographic materials using various known dispersion methods.

With the photographic materials according to this invention, it ispreferable to provide, where suitable, protective layers, intermediatelayers, filter layers, antihalation layers, backing layers, white lightreflection layers and other such auxiliary layers in addition to thesilver halide emulsion layers.

In such cases, in this invention, it is preferable that the distancebetween the layer containing the aforementioned emulsions of thisinvention and the photographic material surface is 25 μm or less, and itis further preferable that the film swelling rate is 2 or more (in thedevelopment processing solution).

With the photographic materials of this invention, the photographicemulsion layers and the other layers are coated onto the supportsdisclosed in Research Disclosure, No. 17643, section V-VII (December,1978), p. 28 and in European Patent 0,102,253 and JP-A-61-97655.Moreover, it is possible to use the coating method disclosed in ResearchDisclosure, No. 17643, section XV, pp. 28 and 29.

This invention can also be applied to multi-layered polychromaticphotographic materials having at least two layers of differing spectralsensitivities on the support. Natural colored multilayered photographicmaterials usually have at least one red-sensitive emulsion layer,green-sensitive emulsion layer and blue-sensitive emulsion layerrespectively on the support. The order of these layers is selectedarbitrarily as required. The order of preferred layer sequences are,from the support, red-sensitive, green-sensitive, blue-sensitive or,from the support, green-sensitive, red-sensitive, blue-sensitive.Furthermore, the various emulsion layers mentioned previously may becomposed of emulsion layers with two or more different sensitivities andthere may be non-photosensitive layers between two or more emulsionlayers which have the same color sensitivity. It is usual to include acyan-forming coupler in the red-sensitive emulsion layer, amagenta-forming coupler in the green-sensitive emulsion layer and ayellow-forming coupler in the blue-sensitive emulsion layer, butdifferent combinations can be adopted according to circumstances.

Various color-photosensitive materials are suitable for use with thisinvention.

For example, color reversal films, color reversal papers, instant colorfilms for slides and television and the like can be cited asrepresentative examples. Furthermore, they can also be suitably used ashard color copies for preserving CRT and full color copier images. Thisinvention is also suitable for use in black-and-white photographicmaterials employing a three color coupler mixture disclosed, forexample, in Research Disclosure, No. 17123 (July, 1978).

The color developing solutions which are used in the developmentprocessing of the photographic materials of this invention arepreferably alkaline aqueous solutions with primary aromatic amine-typecolor developing agents for their main constituents. Aminophenol-typecompounds are useful as these color development agents butp-phenylenediamine-type compounds are preferably used, andrepresentative examples of these include3-methyl-4-amino-N,N-diethylaniline,3-methyl-4-amino-N-ethyl-N-β-hydroxyethylaniline,3-methyl-4-amino-N-ethyl-N-β-methanesulfonamidoethylaniline,3-methyl-4-amino-N-ethyl-N-β-methoxyethylaniline and the sulfuric acidsalts, hydrochloric acid salts or p-toluenesulfonic acid salts thereof.Two or more of these compounds can be used together according to theobjective.

When reversal processing is to be carried out, the color development iseffected after carrying out the usual black-and-white development. Forthis black-and-white developing solution, it is possible to use knownblack-and-white developing agents such as dihydroxy-benzenes (forexample, hydroquinone), 3-pyrazolidones (for example,1-phenyl-3-pyrazolidone) or aminophenols (for example,N-methyl-p-aminophenol) either singly or in combination.

The pH of these color developing solutions and black-and-whitedeveloping solutions is generally between 9 and 12.

Bleach processing is normally carried out on the photographic emulsionlayers after color development. The bleach processing may be carried outat the same time as a fixing process (bleach-fixing process) or it maybe carried out separately. In addition, the processing method in whichbleach-fixing processing is carried out after the bleaching process maybe undertaken in order to accelerate the processing.

The silver halide color photographic materials of this invention willgenerally undergo washing and/or stabilization stages after adesilvering process.

The pH of the washing water in the processing of the photographicmaterials of this invention is between 4 and 9, preferably 5 and 8.

Color developing agents may be incorporated into the silver halide colorphotographic materials of this invention with a view to simplifying andaccelerating processing. For the incorporation, it is preferable to usevarious precursors of the color developing agents.

The various processing solutions in this invention are used at 10° C. to50° C. Normally, a temperature of 33° C. to 40° C. will be standard butit is possible to accelerate the processing and reduce the processingtime by having higher temperatures, or, conversely, to achieve animprovement in the image quality and in the stability of the processingsolution by having lower temperatures.

It is possible to use the various known developing agents in order todevelop black-and-white photographic materials in this invention. Thus,it is possible to use, either singly or in combination,polyhydroxybenzenes (for example, hydroquinone, 2-chlorohydroquinone,2-methylhydroquinone, catechol, pyrogallol); aminophenols (for example,p-aminophenol, N-methyl-p-aminophenol, 2,4-diaminophenol);3-pyrazolidones (for example, 1-phenyl-3-pyrazolidone,1-phenyl-4,4'-dimethyl-3-pyrazolidone,1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone,5,5-dimethyl-1-phenyl-3-pyrazolidone) and ascorbic acids. Furthermore,it is possible to use the developing solution disclosed inJP-A-58-55928.

Detailed specific examples of developing agents, preservatives,buffering agents and development methods for black-and-whitephotographic materials and methods for the use thereof are disclosed,for example, in Research Disclosure, No. 17643 (December, 1978), sectionXIX-XXI.

The invention is explained in further detail below making use ofexamples, but the invention is not limited by these examples.

Unless otherwise specified, all ratios, percents, etc., are by weight.

EXAMPLE 1

The eight types of silver iodobromide emulsions shown in Table 1 wereprepared (grain size 0.3 μm)

                  TABLE 1                                                         ______________________________________                                                               Peak Value of                                                      Average    Latent Image                                                       AgI Content                                                                              Distribution                                           Emulsion    (mol %)    (μm)                                                ______________________________________                                        A           9          0.008                                                  B           9          0                                                      C           4          0.008                                                  D           6          "                                                      E           14         "                                                      F           20         "                                                      G           9          0.003                                                  H           9          0.012                                                  ______________________________________                                    

The production methods for these emulsions are given below.

Emulsion A:

A monodispersed emulsion having a (100) crystal habit was prepared byadding a 15% silver nitrate solution and an aqueous solution containingKBr and KI to an aqueous gelatin solution (0.037%) maintained at 72° C.,using the double jet method over 47 minutes, while maintaining thesilver potential (SCE) at +90 mV. Thus, the core emulsion was obtained.Following this, sodium thiosulfate and sodium chloroaurate were added tothe core emulsion as chemical sensitizers and chemical ripening wascarried out for 55 minutes. The temperature was then reduced to 50° C.and the final size was made 0.3 μm and the average silver iodide content9 mol % by shell deposition for 7 minutes again adding a 15% silvernitrate solution and an aqueous solution containing KBr and KI. The peakvalue of the latent image distribution was at a depth 0.008 μm from thesurface.

Emulsion B:

Shell deposition was carried out on the same core emulsion as inEmulsion A and under the same conditions as for Emulsion A and thenchemical sensitization was carried out.

Emulsions C, D, E, F:

Emulsions with the same latent image distribution as Emulsion A and withaverage silver iodide contents of 4, 6, 14 and 20 mol % were preparedwith the same methods as for Emulsion A and these were Emulsions C, D,E, F.

Emulsion G:

Emulsion G was prepared under the same conditions as for Emulsion Aexcept that the core addition time was extended to 53 minutes and theshell addition time was 3 minutes, in other words the core/shell ratiowas adjusted under similar conditions to those for Emulsion A. The peakvalue of the latent image distribution of this emulsion was at a depth0.003 μm from the surface.

Emulsion H:

Emulsion H was prepared under the same conditions as for Emulsion A witha core addition time of 43 minutes and a shell addition time of 12minutes. The peak value of the latent image distribution of thisemulsion was at a depth 0.012 μm from the surface.

Sensitizing Dye S-1 was added to the above emulsions and coated ontocellulose triacetate film supports in an amount of 2 g of silver per m²,respectively.

The above films were exposed for 1/100 second through either a bluefilter (BPN-42) or through a minus blue filter (SC-39) and developmentprocessing was carried out under the processing conditions given below.

The sensitometry results so obtained are shown in Table 2. Here, thesensitivity is shown as the value corresponding to the reciprocal of theexposure which gives a density of fogging +0.1.

Furthermore, the graininess is shown by the value at a density of 1.0using the customary RMS measurement values when the sensitizing dye isused in an amount of 0.2 mmol/mol Ag and minus blue exposure isconducted. The results are shown in Table 2.

It will be seen from the results that the photographic materialscontaining emulsions having the specific average silver iodide contentand the latent image distribution of this invention are superior to thecomparative emulsions in their sensitivity, graininess and storageproperties.

For example, the average silver iodide content of Emulsions C, D, E andF is different to that of this invention and they are inferior to thisinvention in their sensitivity and graininess. Furthermore, the latentimage distribution of Emulsions B and H is different to that of thisinvention and they are inferior to the emulsions of this invention intheir sensitivity and storage properties.

Processing Conditions:

Processing for 4 minutes at 30° C. in a processing solution composed of:

    ______________________________________                                        1-Phenyl-3-pyrazolidone  0.5    g                                             Hydroquinone             10     g                                             Ethylenediaminetetraacetic Acid                                                                        2      g                                             Disodium Salt                                                                 Potassium Sulfite        60     g                                             Boric Acid               4      g                                             Potassium Carbonate      20     g                                             Sodium Bromide           5      g                                             Diethylene Glycol        20     g                                             Sodium Hydroxide to adjust pH to                                                                       10.0                                                 Water to make            1      liter                                         ______________________________________                                    

                                      TABLE 2                                     __________________________________________________________________________                        Minus                                                                              Relative Sensi-                                                     Blue Blue tivity after                                                        Exposure                                                                           Exposure                                                                           Storage for                                                         Relative                                                                           Relative                                                                           3 Days at 50° C.                                     Dye     Sensi-                                                                             Sensi-                                                                             Following                                                                              RMS                                         Emulsion                                                                             (mmol/mol Ag)                                                                         tivity                                                                             tivity                                                                             Blue Exposure                                                                          Value                                       __________________________________________________________________________    A      --      113  --   94                                                   (Invention)                                                                          0.1     106  1,180                                                                              89                                                          0.2     92   1,230                                                                              81       0.019                                              0.4     43     590                                                                              37                                                   B      --      100  --   67                                                   (Comparison)                                                                         0.1     82     940                                                                              61                                                          0.2     57     790                                                                              42       0.018                                              0.4     41     560                                                                              25                                                   C      --      98   --   78                                                   (Comparison)                                                                         0.2     76   1,080                                                                              70       0.022                                       D      --      107  --   86                                                   (Invention)                                                                          0.2     87   1,180                                                                              76       0.020                                       E      --      105  --   83                                                   (Invention)                                                                          0.2     84   1,120                                                                              74       0.018                                       F      --      94   --   75                                                   (Comparison)                                                                         0.2     70     950                                                                              62       0.019                                       G      --      114  --   92                                                   (Invention)                                                                          0.2     90   1,190                                                                              77       0.018                                       H      --      92   --   76                                                   (Comparison)                                                                         0.2     71     930                                                                              62       0.023                                       __________________________________________________________________________

EXAMPLE 2

A multilayer color photosensitive material composed of various layerswith the compositions shown below was prepared on a cellulose triacetatesupport which had undergone an undercoating treatment.

    ______________________________________                                        Layer 1: Antihalation Layer                                                   Black Colloidal Silver  0.25    g/m.sup.2                                     Ultraviolet Absorber U-1                                                                              0.1     g/m.sup.2                                     Ultraviolet Absorber U-2                                                                              0.1     g/m.sup.2                                     High Boiling Point Organic Solvent,                                                                   0.1     cc/m.sup.2                                    Oil-1                                                                         Gelatin                 1.9     g/m.sup.2                                     Layer 2: Intermediate Layer 1                                                 Compound Cpd D          10      mg/m.sup.2                                    High Boiling Point Organic Solvent,                                                                   40      mg/m.sup.2                                    Oil-3                                                                         Gelatin                 0.4     g/m.sup.2                                     Layer 3: Intermediate Layer 2                                                 Surface-Fogged Fine-Grained Silver                                                                    0.05    g/m.sup.2                                     Iodobromide Emulsion (average grain size:                                                             (as silver)                                           0.06 μm, AgI content: 1 mol %)                                             Gelatin                 0.4     g/m.sup.2                                     Layer 4: First Red-Sensitive Emulsion Layer                                   Silver Iodobromide Emulsion Spectrally                                                                0.4     g/m.sup.2                                     Sensitized with Sensitizing Dyes S-1 and                                                              (as silver)                                           S-2 (average grain size: 0.2 μm,                                           AgI content: 5 mol %)                                                         Coupler C-1             0.2     g/m.sup.2                                     Coupler C-2             0.05    g/m.sup.2                                     High Boiling Point Organic Solvent,                                                                   0.1     cc/m.sup.2                                    Oil-1                                                                         Gelatin                 0.8     g/m.sup.2                                     Layer 5: Second Red-Sensitive Emulsion Layer                                  Silver Iodobromide (mentioned in                                                                      0.4     g/m.sup.2                                      Table 3) Spectrally Sensitized by                                                                    (as silver)                                           Sensitizing Dyes S-1 and S-2                                                  Coupler C-1             0.2     g/m.sup.2                                     Coupler C-3             0.2     g/m.sup.2                                     Coupler C-2             0.05    g/m.sup.2                                     High Boiling Point Organic Solvent,                                                                   0.1     cc/m.sup.2                                    Oil-1                                                                         Gelatin                 0.8     g/m.sup.2                                     Layer 6: Third Red-Sensitive Emulsion Layer                                   Silver Iodobromide Emulsion                                                                           0.4     g/m.sup.2                                     (a spherical multidispersed emulsion with                                                             (as silver)                                           an average grain size of 0.7 μm and an AgI                                 content of 2 mol %) Spectrally Sensitized                                     with Sensitizing Dyes S-1 and S-2                                             Coupler C-3             0.7     g/m.sup.2                                     Gelatin                 1.1     g/m.sup.2                                     Layer 7: Intermediate Layer 3                                                 Dye D-1                 0.02    g/m.sup.2                                     Gelatin                 0.6     g/m.sup.2                                     Layer 8: Intermediate Layer 4                                                 A Surface-Fogged Fine-Grained Silver                                                                  0.05    g/m.sup.2                                     Iodobromide Emulsion (average grain size:                                                             (as silver)                                           0.06 μm, AgI Content: 1 mol %)                                             Compound Cpd A          0.2     g/m.sup.2                                     Gelatin                 1.0     g/m.sup.2                                     Layer 9: First Green-Sensitive Emulsion Layer                                 Silver Iodobromide Emulsion (average                                                                  0.5     g/m.sup.2                                     grain size: 0.2 μm, AgI content: 5 mol %)                                                          (as silver)                                           Spectrally Sensitized with Sensitizing                                        Dyes S-3 and S-4                                                              Coupler C-4             0.3     g/m.sup.2                                     Compound Cpd B          0.03    g/m.sup.2                                     Gelatin                 0.5     g/m.sup.2                                     Layer 10: Second Green-Sensitive Emulsion Layer                               Silver Iodobromide Emulsion                                                                           0.4     g/m.sup.2                                     (a monodispersed cubic emulsion with an                                                               (as silver)                                           average grain size of 0.4 μm, AgI content:                                 3 mol %) Containing Sensitizing Dyes S-3                                      and S-4                                                                       Coupler C-4             0.3     g/m.sup.2                                     Compound Cpd B          0.03    g/m.sup.2                                     Gelatin                 0.6     g/m.sup.2                                     Layer 11: Third Green-Sensitive Emulsion Layer                                Silver Iodobromide Emulsion (tabular                                                                  0.5     g/m.sup.2                                     emulsion, average grain size: 0.7 μm,                                                              (as silver)                                           aspect ratio: 3, AgI content: 2 mol %)                                        Containing Sensitizing Dyes S-3 and S-4                                       Coupler C-4             0.8     g/m.sup.2                                     Compound Cpd B          0.08    g/m.sup.2                                     Gelatin                 1.0     g/m.sup.2                                     Layer 12: Intermediate Layer 5                                                Dye D-2                 0.05    g/m.sup.2                                     Gelatin                 0.6     g/m.sup.2                                     Layer 13: Yellow Filter Layer                                                 Yellow Colloidal Silver 0.1     g/m.sup. 2                                    Compound Cpd A          0.01    g/m.sup.2                                     Gelatin                 1.1     g/m.sup.2                                     Layer 14:                                                                     Gelatin                 1.1     g/m.sup.2                                     Layer 15: First Blue-Sensitive Emulsion Layer                                 Silver Iodobromide Emulsion                                                                           0.6     g/m.sup.2                                     (monodispersed cubic emulsion, average                                                                (as silver)                                           grain size: 0.5 μm, AgI content: 3 mol %)                                  Containing Sensitizing Dyes S-5 and S-6                                       Coupler C-5             0.6     g/m.sup.2                                     Gelatin                 0.8     g/m.sup.2                                     Layer 16: Second Blue-Sensitive Emulsion Layer                                Silver Iodobromide Emulsion (tabular                                                                  0.4     g/m.sup.2                                     emulsion, average grain size: 0.6 μm,                                                              (as silver)                                           aspect ratio: 7, AgI Content: 2 mol %)                                        Containing Sensitizing Dyes S-5 and S-6                                       Coupler C-5             0.3     g/m.sup.2                                     Coupler C-6             0.3     g/m.sup.2                                     Gelatin                 0.9     g/m.sup.2                                     Layer 17: Third Blue-Sensitive Emulsion Layer                                 Silver Iodobromide Emulsion (tabular                                                                  0.4     g/m.sup.2                                     emulsion, average grain size: 1.0 μm,                                                              (as silver)                                           aspect ratio: 7, AgI Content: 2 mol %)                                        Containing Sensitizing Dyes S-5 and S-6                                       Coupler C-6             0.7     g/m.sup.2                                     Gelatin                 1.2     g/m.sup.2                                     Layer 18: First Protective Layer                                              Ultraviolet Absorber U-1                                                                              0.04    g/m.sup.2                                     Ultraviolet Absorber U-3                                                                              0.03    g/m.sup.2                                     Ultraviolet Absorber U-4                                                                              0.03    g/m.sup.2                                     Ultraviolet Absorber U-5                                                                              0.05    g/m.sup.2                                     Ultraviolet Absorber U-6                                                                              0.05    g/m.sup.2                                     Compound Cpd C          0.8     g/m.sup.2                                     Dye D-3                 0.05    g/m.sup.2                                     Gelatin                 0.7     g/m.sup.2                                     Layer 19: Second Protective Layer                                             Surface-Fogged Fine-Grained Silver                                                                    0.1     g/m.sup.2                                     Iodobromide Emulsion (average grain size:                                                             (as silver)                                           0.06 μm, AgI content: 1 mol %)                                             Polymethyl Methacrylate Particles                                                                     0.1     g/m.sup.2                                     (average particle size: 1.5 μm)                                            A 4/6 (molar ratio) Copolymer of Methyl                                                               0.1     g/m.sup.2                                     Methacrylateand Acrylic Acid (average                                         particle size: 1.5 μm)                                                     Compound Cpd E          0.03    g/m.sup.2                                     Fluorine-Containing Surfactant W-1                                                                    3       mg/m.sup.2                                    Gelatin                 2.1     g/m.sup.2                                     ______________________________________                                    

In addition to the above constituents, Gelatin Hardening Agent H-1 andsurfactants were added to the various layers.

Samples 201 and 202 were prepared using Emulsion A and Emulsion B ofExample 1 in Layer 5 of the above sample.

These Samples 201 and 202 were each subjected to a wedge exposure withred light and the other portions were subjected to a wedge exposure withwhite (red +green +blue) light. The quantity of red light during thewhite exposure was the same as during the red exposure.

The samples which had undergone these exposures were subjected to thedevelopment processing shown below. The results are given in Table 3.

A greater difference in the exposure for a density equal to 1.0 in thecomparison of the cyan of the red exposure part and the cyan of thewhite exposure part represents a larger interimage effect.

    ______________________________________                                        Processing                                                                                   Time                                                           Stage          (min)   Temperature                                            ______________________________________                                        First Development                                                                            6       38° C.                                          Washing        2       "                                                      Reversal       2       "                                                      Color Development                                                                            6       "                                                      Conditioning   2       "                                                      Bleaching      6       "                                                      Fixing         4       "                                                      Washing        4       "                                                      Stabilization  1       Room Temperature                                       Drying                                                                        ______________________________________                                    

The following substances were used in the composition of the processingsolutions.

    ______________________________________                                        First Development Solution:                                                   Water                     700    ml                                           Nitrilo-N,N,N-trimethylenephosphonic                                                                    2      g                                            Acid Pentasodium Salt                                                         Sodium Sulfite            20     g                                            Hydroquinone Monosulfonate                                                                              30     g                                            Sodium Carbonate (monohydrate)                                                                          30     g                                            1-Phenyl-4-methyl-4-hydroxymethyl-3-                                                                    2      g                                            pyrazolidone                                                                  Potassium Bromide         2.5    g                                            Potassium Thiocyanate     1.2    g                                            Potassium Iodide (0.1% solution)                                                                        2      ml                                           Water to make             1,000  ml                                           Reversal Solution:                                                            Water                     700    ml                                           Nitrilo-N,N,N-trimethylenephosphonic                                                                    3      g                                            Acid Pentasodium Salt                                                         Stannous Chloride (dihydrate)                                                                           1      g                                            p-Aminophenol             0.1    g                                            Sodium Hydroxide          8      g                                            Glacial Acetic Acid       15     ml                                           Water to make             1,000  ml                                           Color Developing Solution:                                                    Water                     700    ml                                           Nitrilo-N,N,N-trimethylenephosphonic                                                                    3      g                                            Acid Pentasodium Salt                                                         Sodium Sulfite            7      g                                            Sodium Triphosphate (dodecahydrate)                                                                     36     g                                            Potassium Bromide         1      g                                            Potassium Iodide (0.1% solution)                                                                        90     ml                                           Sodium Hydroxide          3      g                                            Citrazinic Acid           1.5    g                                            N-Ethyl-N-(β-methanesulfonamidoethyl)-                                                             11     g                                            3-methyl-4-aminoaniline Sulfate                                               3,6-Dithiaoctane-1,8-diol 1      g                                            Water to make             1,000  ml                                           Adjustment Solution                                                           Water                     700    ml                                           Sodium Sulfite            12     g                                            Ethylenediaminetetraacetic Acid                                                                         8      g                                            Sodium Salt (dihydrate)                                                       Thioglycerin              0.4    ml                                           Glacial Acetic Acid       3      ml                                           Water to make             1,000  ml                                           Bleaching Solution:                                                           Water                     800    ml                                           Ethylenediaminetetraacetic Acid                                                                         2      g                                            Sodium Salt (dihydrate)                                                       Ethylenediaminetetraacetic Acid                                                                         120    g                                            Iron (III) Ammonium Salt (dihydrate)                                          Potassium Bromide         100    g                                            Water to make             1,000  ml                                           Fixing Solution                                                               Water                     800    ml                                           Sodium Thiosulfate        80.0   g                                            Sodium Sulfite            5.0    g                                            Sodium Bisulfite          5.0    g                                            Water to make             1,000  ml                                           Stabilization Solution:                                                       Water                     800    ml                                           Formalin (37%)            5.0    ml                                           Fuji Driwel (surfactant made by                                                                         5.0    ml                                           Fuji Photo Film Co., Ltd.)                                                    Water to make             1,000  ml                                           ______________________________________                                    

The color reversal sensitivities were compared on the basis of therelative exposure giving a density of 1.0 greater than the maximumdensity.

                  TABLE 3                                                         ______________________________________                                                            Relative Red                                                        Emulsion  Sensitivity Δ Log E for a                                     Used in   in the White                                                                              Cyan Density =                                Sample No.                                                                              Layer 5   Exposed Part                                                                              1.0                                           ______________________________________                                        201       A         100         0.21                                          (Invention)                                                                   202       B          82         0.05                                          (Comparison)                                                                  ______________________________________                                    

As indicated above, it will be seen that the sample which used anemulsion having the silver diode content and latent image distributionof this nveniton exhibits superior reversal sensitivity and produces adramatically greater interimage effect than the sample of thecomparative sample.

The structural formulae of compounds used in Example 2 are given below.##STR1##

EXAMPLE 3

Samples 301 to 303, which contain Emulsions A, B and C disclosed for thefirst red-sensitive layer of the multilayered color-sensitive materialsample of Example 1, were prepared by multilayer coating of the variouslayers with the compositions shown below onto cellulose triacetate filmsupports which had undergone undercoating treatment.

    ______________________________________                                        Layer 1: Antihalation Layer                                                   Black Colloidal Silver   0.18 g/m.sup.2 (Ag)                                  Gelatin                  1.40 g/m.sup.2                                       Layer 2: Intermediate Layer                                                   2,5-Di-t-pentadecylhydroquinone                                                                        0.18 g/m.sup.2                                       C-11                     0.07 g/m.sup.2                                       C-13                     0.02 g/m.sup.2                                       U-11                     0.08 g/m.sup.2                                       U-12                     0.08 g/m.sup.2                                       Oil-2                    0.10 g/m.sup.2                                       Oil-1                    0.02 g/m.sup.2                                       Gelatin                  1.0 g/m.sup.2                                        Layer 3: First Red-Sensitive Emulsion Layer                                   Silver Iodobromide Emulsion                                                                            0.50 g/m.sup.2 (Ag)                                  Spectrally Sensitized by Sensitizing                                          Dyes S-11, S-12, S-13 and S-18                                                (Emulsions A, B and C disclosed in                                            Example 1)                                                                    C-12                     0.14 g/m.sup.2                                       Oil-2                    0.005 g/m.sup.2                                      C-20                     0.005 g/m.sup.2                                      Gelatin                  1.20 g/m.sup.2                                       Layer 4: Second Red-Sensitive Emulsion Layer                                  Silver Iodobromide Emulsion                                                                            1.15 g/m.sup.2 (Ag)                                  Spectrally Sensitized by Sensitizing                                          Dyes S-11, S-12, S-13 and S-18                                                (amorphous multiple twin crystal grains                                       having a sphere-equivalent average                                            grain size of 0.6 μm, iodine content:                                      2 mol %)                                                                      C-12                     0.060 g/m.sup.2                                      C-13                     0.008 g/m.sup.2                                      C-20                     0.004 g/m.sup.2                                      Oil-2                    0.005 g/m.sup.2                                      Gelatin                  1.50 g/m.sup.2                                       Layer 5: Third Red-Sensitive Emulsion Layer                                   Silver Iodobromide Emulsion                                                                            1.50 g/m.sup.2 (Ag)                                  Spectrally Sensitized by Sensitizing                                          Dyes S-11, S-12, S-13 and S-18                                                (amorphous multiple twin crystal grains                                       having a sphere-equivalent average                                            grain size of 0.8 μm, iodine content:                                      2 mol %)                                                                      C-15                     0.012 g/m.sup.2                                      C-13                     0.003 g/m.sup.2                                      C-14                     0.004 g/m.sup.2                                      Oil-2                    0.32 g/m.sup.2                                       Gelatin                  1.63 g/m.sup.2                                       Layer 6: Intermediate layer                                                   Gelatin                  1.06 g/m.sup.2                                       Layer 7: First Green-Sensitive Emulsion Layer                                 Silver Iodobromide Emulsion                                                                            0.35 g/m.sup.2 (Ag)                                  Spectrally Sensitized with Sensitizing                                        Dyes S-14, S-15 and S-16 (amorphous                                           multiple twin crystal grains having a                                         sphere-equivalent average grain size                                          of 0.3 μm, iodine content: 2 mol %)                                        C-16                     0.120 g/m.sup.2                                      C-11                     0.021 g/m.sup.2                                      C-17                     0.030 g/m.sup.2                                      C-18                     0.025 g/m.sup.2                                      Oil-2                    0.20 g/m.sup.2                                       Gelatin                  0.70 g/m.sup.2                                       Layer 8: Second Green-Sensitive Emulsion Layer                                Silver Iodobromide Emulsion                                                                            0.75 g/m.sup.2 (Ag)                                  Spectrally Sensitized by Sensitizing                                          Dyes S-14, S-15 and S-16 (amorphous                                           multiple twin crystal grains having a                                         sphere-equivalent average grain size                                          of 0.6 μm, iodine content: 2 mol %)                                        C-16                     0.021 g/m.sup.2                                      C-18                     0.004 g/m.sup.2                                      C-11                     0.002 g/m.sup.2                                      C-17                     0.003 g/m.sup.2                                      Oil-2                    0.15 g/m.sup.2                                       Gelatin                  0.80 g/m.sup.2                                       Layer 9: Third Green-Sensitive Emulsion Layer                                 Silver Iodobromide Emulsion                                                                            1.80 g/m.sup.2 (Ag)                                  Spectrally Sensitized by Sensitizing                                          Dyes S-14, S-15 and S-16 (amorphous                                           multiple twin crystal grains having a                                         sphere-equivalent average grain size                                          of 0.2 μm, iodine content: 2 mol %)                                        C-16                     0.011 g/m.sup.2                                      C-11                     0.001 g/m.sup.2                                      Oil-1                    0.69 g/m.sup.2                                       Gelatin                  1.74 g/m.sup.2                                       Layer 10: Yellow Filter Layer                                                 Yellow Colloidal Silver  0.05 g/m.sup.2 (Ag)                                  2,5-Di-t-pentadecylhydroquinone                                                                        0.03 g/m.sup.2                                       Gelatin                  0.95 g/m.sup.2                                       Layer 11: First Blue-Sensitive Emulsion Layer                                 Silver Iodobromide Emulsion                                                                            0.24 g/m.sup.2 (Ag)                                  Spectrally Sensitized by Sensitizing                                          Dye S-17 (amorphous multiple twin crystal                                     grains having a sphere-equivalent average                                     grain size of 0.3 μm, iodine content:                                      2 mol %)                                                                      C-19                     0.27 g/m.sup.2                                       C-18                     0.005 g/m.sup.2                                      Oil-2                    0.28 g/m.sup.2                                       Gelatin                  1.28 g/m.sup.2                                       Layer 12: Second Blue-Sensitive Emulsion Layer                                Silver Iodobromide Emulsion                                                                            0.45 g/m.sup.2 (Ag)                                  Spectrally Sensitized by Sensitizing                                          Dye S-17 (amorphous multiple twin crystal                                     grains having a sphere-equivalent average                                     grain size of 0.6 μm, iodine content:                                      2 mol %)                                                                      C-19                     0.098 g/m.sup.2                                      Oil-2                    0.03 g/m.sup.2                                       Gelatin                  0.46 g/m.sup.2                                       Layer 13: Third Blue-Sensitive Emulsion Layer                                 Silver Iodobromide Emulsion                                                                            0.77 g/m.sup.2 (Ag)                                  Spectrally Sensitized by Sensitizing                                          Dye S-17 (amorphous multiple twin crystal                                     grains having a sphere-equivalent average                                     grain size of 0.8 μm, iodine content:                                      2 mol %)                                                                      C-19                     0.036 g/m.sup.2                                      Oil-2                    0.07 g/m.sup.2                                       Gelatin                  0.69 g/m.sup.2                                       Layer 14: First Protective layer                                              Silver Iodobromide       0.5 g/m.sup.2 (Ag)                                   (silver iodide: 1 mol %, average                                              grain size: 0.07 μm)                                                       U-11                     0.11 g/m.sup.2                                       U-12                     0.17 g/m.sup.2                                       Oil-2                    0.90 g/m.sup.2                                       Layer 15: Second Protective Layer                                             Polymethyl Methacrylate Particles                                                                      0.54 g/m.sup.2                                       (diameter: about 1.5 μm)                                                   U-13                     0.15 g/m.sup.2                                       U-14                     0.10 g/m.sup.2                                       Gelatin                  0.72 g/m.sup.2                                       ______________________________________                                    

In addition to the above constituents, Gelatin Hardening Agent H-1 andsurfactants were added to each layer.

Sample Nos. 301 to 303 obtained in this way were given a white lightwedge exposure and the development processing shown below was carriedout.

    ______________________________________                                        Processing Stage (38° C.)                                                                Processing Time                                             ______________________________________                                        Color Development 3 min 15 sec                                                Bleaching         6 min 30 sec                                                Washing           2 min 10 sec                                                Fixing            4 min 20 sec                                                Washing           3 min 15 sec                                                Stabilization     1 min 05 sec                                                ______________________________________                                    

The processing solution compositions used in the processing stages wereas shown below.

    ______________________________________                                        Color Developing Solution:                                                    Diethylenetriaminepentaacetic Acid                                                                    1.0 g                                                 1-Hydroxyethylidene-1,1-diphosphonic                                                                  2.0 g                                                 Acid                                                                          Sodium Sulfite          4.0 g                                                 Potassium Carbonate     30.0 g                                                Potassium Bromide       1.4 g                                                 Potassium Iodide        1.3 mg                                                Hydroxylamine Sulfate   2.4 g                                                 4-(N-Ethyl-N-β-hydroxyethylamino)-2-                                                             4.5 g                                                 methylaniline Sulfate                                                         Water to make           1.0 liter                                             pH                      10.0                                                  Bleaching Solution:                                                           Ethylenediaminetetraacetic Acid                                                                       100.0 g                                               Ferric Ammonium Salt                                                          Ethylenediaminetetraacetic Acid                                                                       10.0 g                                                Disodium Salt                                                                 Ammonium Bromide        150.0 g                                               Ammonium Nitrate        10.0 g                                                Water to make           1.0 liter                                             pH                      6.0                                                   Fixing Solution:                                                              Ethylenediaminetetraacetic Acid                                                                       1.0 g                                                 Disodium Salt                                                                 Sodium Sulfite          4.0 g                                                 Aqueous Ammonium Thiosulfate Solution                                                                 175.0 ml                                              (70%)                                                                         Sodium Bisulfite        4.6 g                                                 Water to make           1.0 liter                                             pH                      6.6                                                   Stabilization Solution:                                                       Formalin (40%)          2.0 ml                                                Polyoxyethylene-p-monononylphenyl                                                                     0.3 g                                                 Ether (average degree of polymeriza-                                          tion: 10)                                                                     Water to make           1.0 liter                                             ______________________________________                                    

The color negative sensitivity of the first red-sensitive layer wasassessed on the basis of the relative exposures which are 2.0 greaterthan the minimum densities of the magenta density and yellow density.The effects of this invention are clearly evident in these results;Sample 301 having a higher sensitivity and better storage propertiesthan Comparative Samples 302 and 303.

The structural formulae of the compounds used in Example 3 are shownbelow. ##STR2##

EXAMPLE 4

The 41 types of silver iodobromide emulsions shown in Table 4 wereprepared. The method of producing of these emulsions is given below.

A cubic emulsion was prepared by adding a silver nitrate solution and anaqueous solution containing KBr and KI to an aqueous gelatin solutionmaintained at 70° C., using the double jet method, while maintaining thepBr at 3.3. This core emulsion was then divided and shells formedseparately under the conditions shown below, the size of the finalgrains was 0.3 μm and the AgI content was 5 mol %.

Emulsion 5

Chemical sensitization was carried out by adding sodium thiosulfate andpotassium chloroaurate to the above core. A shell was then depositedunder the same conditions as for the core formation.

Emulsions 1, 2, 3, 4 and 6

Emulsions were prepared in the same way as for Emulsion 5 except that,of the potassium halides added during the shell formation, 1, 2, 3, 4and 6 mol % of KI were used; these were Emulsions 1, 2, 3, 4 and 6.

Emulsions 7 and 8

Emulsions 7 and 8 were prepared in the same way as for Emulsions 3 and 5except that chemical sensitization was only carried out after the shelldeposition.

Emulsions 9 and 10

Emulsions were prepared in the same way as for Emulsions 3 and 5 exceptthat the pBr value was lowered to 2.8 and shell deposition was carriedout under conditions of a lowered silver halide solubility; these wereEmulsions 9 and 10.

Emulsions 11 to 17

Emulsions were prepared in the same way as for Emulsions 2, 3, 4, 7 and9 except that, of the potassium halides added during the core grainformation, 3 mol % of KI were used; these were Emulsions 11, 12, 13, 15and 17. In addition, Emulsions 14 and 16 were prepared in the same wayas Emulsions 15 and 17 except that 2 mol % of KI were used whendepositing the shell.

Emulsions 18 to 27

Emulsions 18 to 27 were prepared in the same way as Emulsions 1 to 10except that the pBr was 4.5 during the core grain formation.

Emulsions 28 to 37

Emulsions 28 to 37 were prepared in the same way as Emulsions 1 to 10except that the size of the core grains was made larger.

Emulsions 38 to 41

Emulsions 39 to 41 (aspect ratio 5.0) were prepared in the same way asEmulsions 12 and 17 except that tabular grains were used as the coregrains. Additionally, Emulsions 38 and 40 were prepared using 1 mol % ofKI during the shell formation.

Sensitizing Dye S-1 shown in Example 2 was added to the above Emulsions1 to 41, at 0.4 mmol/mol Ag for 1 to 27, and at 0.2 mmol/mol Ag for 28to 41 and these were coated at 2 μg of silver per square centimeterproducing Samples 101 to 141.

The above films were exposed for 10 seconds, 1/100 second, 1/100,000second through a blue filter (BPN-42) or for 1/100 second through aminus blue filter (SC-39) and development processing was carried outusing the processing solution shown below.

The sensitometry results so obtained are shown in Table 4. Here, thesensitivity is shown as the relative value of the reciprocal of theexposure which provides a density of fogging +0.1.

It will be seen from the results that the photographic materialscontaining emulsions having the specific latent image distribution andsilver iodide distribution of this invention are better in theirsensitivities and latent image storage properties than the otheremulsions.

For example, Emulsion 7 is close to the emulsions of this invention inthe depth at which the peak value of its latent image distribution islocated and in the silver iodide distribution within the grain, however,there is a small number of latent images in the surface and a lowersensitivity than the emulsions of this invention is all that isobtained. Furthermore, Emulsion 6 is close to the emulsions of thisinvention in the relationship between the peak value of the latent imagedistribution and the latent image numbers at the surface and in thedepth at which the peak value of its latent image distribution islocated, however, it is different to the emulsions of this invention inthe silver diode distribution within the grain and lower sensitivitiesare all that are obtained.

    ______________________________________                                        Processing Solution:                                                          ______________________________________                                        1-Phenyl-3-pyrazolidone    0.5 g                                              Hydroquinone              10 g                                                Ethylenediaminetetraacetic Acid                                                                          2 g                                                Disodium Salt                                                                 Potassium Sulfite         60 g                                                Boric Acid                 4 g                                                Potassium Carbonate       20 g                                                Sodium Bromide             5 g                                                Diethylene Glycol         20 g                                                Adjusted with Sodium Hydroxide to pH                                                                    10.0                                                Water to make              1 liter                                            ______________________________________                                    

                                      TABLE 4                                     __________________________________________________________________________                                              Logarithm of the                                                                        Change in                                                                     Sensitivity                                              Average                                                                             Surface                                                                            Relative  upon Processing                                                               after                                                    Silver                                                                              Silver                                                                             Sensitivity                                                                             Storage for 3 Days                                       Iodide                                                                              Iodide                                                                             for a Minus                                                                             at 50° C.                                                              Following                               Size      Latent Image                                                                         Content                                                                             Content                                                                            Blue Exposure                                                                           Minus Blue Exposure       Sample No.                                                                             Emulsion                                                                           (μm)                                                                          Grain Form                                                                           Distribution*                                                                        (mol %)                                                                             (mol %)                                                                            (log E)   (Δ log              __________________________________________________________________________                                                        E)                        101 (Invention)                                                                         1   0.3                                                                              Cubic  1      5     1    3.38      -0.03                     102 (Invention)                                                                         2   "  "      "      "     2    3.38      -0.02                     103 (Invention)                                                                         3   "  "      "      "     3    3.37      -0.02                     104 (Invention)                                                                         4   "  "      "      "     4    3.35      -0.03                     105 (Comparison)                                                                        5   "  "      "      "     5    3.30      -0.05                     106 (Comparison)                                                                        6   "  "      "      "     6    3.27      -0.07                     107 (Comparison)                                                                        7   "  "      2      "     3    3.23      -0.06                     108 (Comparison)                                                                        8   "  "      "      "     5    3.18      -0.07                     109 (Comparison)                                                                        9   "  "      3      "     3    3.18      -0.13                     110 (Comparison)                                                                       10   "  "      "      "     5    3.14      -0.14                     111 (Invention)                                                                        11   "  "      1      3     2    3.38      -0.00                     112 (Comparison)                                                                       12   "  "      "      "     3    3.34      -0.02                     113 (Comparison)                                                                       13   "  "      "      "     4    3.31      -0.04                     114 (Comparison)                                                                       14   "  "      2      "     2    3.21      -0.03                     115 (Comparison)                                                                       15   "  "      "      "     3    3.18      -0.03                     116 (Comparison)                                                                       16   "  "      3      "     2    3.24      -0.08                     117 (Comparison)                                                                       17   "  "      "      "     3    3.16      -0.10                     118 (Invention)                                                                        18   "  Octahedral                                                                           1      5     1    3.35      -0.03                     119 (Invention)                                                                        19   "  "      "      "     2    3.35      -0.03                     120 (Invention)                                                                        20   "  "      "      "     3    3.35      -0.03                     121 (Invention)                                                                        21   "  "      "      "     4    3.34      -0.05                     122 (Comparison)                                                                       22   "  "      "      "     5    3.27      -0.07                     123 (Comparison)                                                                       23   "  "      "      "     6    3.22      -0.09                     124 (Comparison)                                                                       24   "  "      2      "     3    3.20      -0.12                     125 (Comparison)                                                                       25   "  "      "      "     5    3.15      -0.14                     126 (Comparison)                                                                       26   "  "      3      "     3    3.15      -0.18                     127 (Comparison)                                                                       27   "  "      "      "     5    3.10      -0.19                     128 (Invention)                                                                        28   0.8                                                                              Cubic  1      "     1    3.19      -0.00                     129 (Invention)                                                                        29   "  "      "      "     2    4.16      -0.00                     130 (Invention)                                                                        30   "  "      "      "     3    4.15      -0.00                     131 (Invention)                                                                        31   "  "      "      "     4    4.14      -0.01                     132 (Comparison)                                                                       32   "  "      "      "     5    4.09      -0.03                     133 (Comparison)                                                                       33   "  "      "      "     6    4.05      -0.05                     134 (Comparison)                                                                       34   "  "      2      "     3    4.04      -0.04                     135 (Comparison)                                                                       35   "  "      "      "     5    3.99      -0.05                     136 (Comparison)                                                                       36   "  "      3      "     3    3.91      -0.09                     137 (Comparison)                                                                       37   "  "      "      "     5    3.87      -0.13                     138 (Invention)                                                                        38   1.1                                                                              Tabular                                                                              1      3     1    4.51      +0.02                     139 (Comparison)                                                                       39   "  "      "      "     3    4.39      -0.04                     140 (Comparison)                                                                       40   "  "      3      "     1    4.17      -0.06                     141 (Comparison)                                                                       41   "  "      "      "     3    4.18      -0.08                     __________________________________________________________________________     *The latent image distribution determined by the method described in this     text was as given below.                                                      1 The latent image distribution of the surface was 0.3 to 0.6 time of the     maximum peak value and the peak value was at a depth of 0.003 μm to        0.006 μm from the surface.                                                 2 The latent image distribution at the surface was 0.1 time or less of th     maximum peak value located within the grain.                                  3 The latent image distribution maximum was at the surface.              

EXAMPLE 5

A multilayer color photosensitive material with layers of the samecomposition as in Example 2 was prepared on a cellulose triacetate filmsupport which had undergone an undercoating in the same way as inExample 2. However, Emulsion 2 of Example 4 was used in Layer 5. Thiswas Sample No. 501.

As is shown in Table 5, Samples 502 to 504 were obtained in the same wayexcept that the emulsions used in Layer 5 were varied.

Exposure and development processing were carried out in the same way asfor Example 2. The results obtained are shown in Table 5.

                  TABLE 5                                                         ______________________________________                                                                  Relative Red                                                      Emulsion Used                                                                             Reversal                                            Sample No.    in Layer 5  Sensitivity                                         ______________________________________                                        501 (Invention)                                                                             2           100                                                 502 (Comparison)                                                                            5           92                                                  503 (Comparison)                                                                            7           85                                                  504 (Comparison)                                                                            9           80                                                  ______________________________________                                    

It will be seen from the above that emulsions having the latent imagedistribution and the silver iodide distribution within the grain of thisinvention exhibit outstanding reversal sensitivities.

While the invention has been described in detail and with reference tospecific embodiments thereof, it will be apparent to one skilled in theart that various changes and modifications can be made therein withoutdeparting from the spirit and scope thereof.

What is claimed is:
 1. A silver halide photographic material comprisingat least one silver halide emulsion layer on a support, wherein thelatent image distribution of silver halide grains present in said atleast one emulsion layer has at least one peak value within said grains,the location of said peak value is at a depth of less than 0.01 μm fromthe surface of the grains, the ratio of the latent image number on theshell surface to the maximum peak value is about 1/5 or more and lessthan 1, and the silver iodide content of the grain surface region is 90%or less of the average content of all of the grains.
 2. The silverhalide photographic material as claimed in claim 6, wherein said atleast one peak value is at a depth of about 0.003 to 0.006 μm from thesurface of the grains.
 3. The silver halide photographic material asclaimed in claim 1, wherein the average silver iodide content of saidgrains is 15 mol % or less.
 4. The silver halide photographic materialas claimed in claim 1, wherein the average silver iodide content of saidgrains is from 3 to 15 mol %.